Study Suggests Antidepressants May Increase Risk of Birth Defects

New research suggests that some antidepressants may increase the risk of birth defects if taken early in pregnancy, though others do not seem to pose the same risks.

Whether antidepressants cause birth defects has been debated for years, and studies have not been conclusive on the question, National Public Radio (NPR) reports. Women and their doctors have a hard time making decisions about how to manage depression during pregnancy.To address the question, researchers at the Centers for Disease Control and Prevention (CDC) analyzed federal data on more than 38,000 women who gave birth from 1997 to 2009. They looked at the number of birth defects among babies and asked the mothers whether they had taken antidepressants in the month before getting pregnant or during the first three months of pregnancy.

The study, published last week in the BMJ, found no association between the most commonly used antidepressant, sertraline (Zoloft), and birth defects. Forty percent of the women who took antidepressants took sertraline. No increased risk for birth defects was found with the antidepressants Celexa (citalopram) and Lexapro (escitalopram). But the analysis did show an association between birth defects and fluoxetine (Prozac) and paroxetine (Paxil). Among the birth defects seen were heart defects, abdominal wall defects, and missing brain and skull defects with paroxetine, and heart wall defects and irregular skull shape with fluoxetine. The relative risk increased 2 to 3.5 times, depending on the defect and the medication.

Jennita Reefhuis, an epidemiologist and lead researcher for the National Birth Defects Prevention Study says, “the overall risk is still small,” NPR reports. The absolute risk of brain and skull malformation (anencephaly) in children of women who took paroxetine early in pregnancy rose from 2 to 7 per 10,000 births. For a heart defect, absolute risk increased from 10 to 24 per 10,000 births. This is an association study and it doesn’t prove that the medications caused birth defects. “If you’re planning to get pregnant, it really is important to talk with your health care provider to see if there are options and if you could choose a safer option among antidepressants,” Reefhuis says. Not all antidepressants work the same for every individual and to women need to consult a health care provider about the appropriate medication.

Dr. Edward McCabe, chief medical officer for the March of Dimes Foundation, said the study’s results must be taken in context. “This paper showed that those antidepressants that appeared to be less safe do not show as high a risk of birth defects as some of the earlier reports showed, so that’s also reassuring.”

Some women may try to wean themselves from antidepressants during pregnancy, some may opt for group or individual talk therapy, and some may switch medications. But McCabe cautions women not to suddenly stop taking antidepressant medication altogether because this “can cause serious risk for the woman, including suicide.” If the woman is pregnant, stress can create “even more risk for the developing fetus than the medication itself.” McCabe notes stress in the mother can increase problems in pregnancy, including premature birth and low birth weight. “[T]he stress of an uncontrolled depression may be putting her baby at significant risk,” McCabe says. McCabe said women should work with their doctors to find a drug that’s safe for their baby and will control their depression, according to NPR.